Ok as promised here is the source.   Its a little rough and ready at the moment but it does deliver that 'web services on devices' experience.

To use you will need to edit the line in OurResponder.cs  to the IP address/port you are listening to, i.e

string thispage = "http://10.100.0.2:8000" + page.ToLower();

Apart from that your good to go.

The little web server needed to be expanded for this all to work to code with MIME types and different HTTP response codes,  but essentially it does not differ from the base web server that I banged on about a couple of days ago.

Source for the complete solution (and yes it does have a UI now) here -

http://www.binaryrefinery.com/main/content/binary/WebServiceForDevice1.zip